Apparatus for resiliently supporting a float pan



June 7, 1966 M. GUNTERT 3,254,577

APPARATUS FOR RESILIENTLY SUPPORTING A FLOAT PAN Filed June 24, 1963 2 Sheets-Sheet 1 FIG. .1.

INVENTOR- RONALD M. GUNTERT ATTORNEYS June 7, 1966 R. M. GUNTERT 3,254,577

APPARATUS FOR RESILIENTLY SUPPORTING A FLOA'T PAN Filed June 24, 1965 2 Sheets-Sheet 2 FIG. 3

INVENTOR. RONALD M. GUNTERT ATTORNEYS & Zimmerman Const. Div., Inc., Stockton, Calif., a corporation of California Filed June 24, 1963, Ser. No. 290,021 3 Claims. (CI. 94-45) This invention relates to paving apparatus for smoothmg and finishing green concrete slabs and the like, and more particularly to a float pan that is partly supported from road building apparatus and other machines by means of a resilient suspension system.

In brief, the present invention comprises a float pan and a resilient support therefor which automatically controls the amount of weight applied to a slab of material as the float pan is being advanced thereover. The resilient support may include a pair of arms that extend rearwardly from a grade controlled paving machine and from which the ends of the float pan are adjustably suspended as by means of a pair of hoists and support springs. The hoists are initially adjusted to tension the springs until only a desired amount of pan weight remains supported by the slab that is being finished. Then, whenever bumps or irregularities are encountered by the leading edge of the pan, a greater portion of the pans weight will be shifted to the underlying slab as to remove the bumps or irregularities. Where the pan is supported from a grade controlled paving machine, there will be little or no change in the proportion of pan weight supported by the slab, even though the slab is laid at various grades and although the grade may change as the machine is advanced. However, interim adjustments of the adjustable supporting means may be made at any time in the event of rapid changes in grade, or if the apparatus should be supported from a machine or platform which is moved vertically by changes in grade.

One primary object of this invention is to provide a float pan and supporting apparatus therefor, which may be used .to produce uniform finishing of a green concrete slab, or other settable material.

Another object is to provide apparatus of the kind described including a float pan that is resiliently and adjustably supported from a traveling machine as by means of hoisting devices and coiled springs.

A further object of the invention is to provide appara tus of the kind decribed, including a float pan supported with an adjustable linkage that permits the distribution of pan weight supported by a slab to be shifted relative to the pans leading and trailing edges, thereby controlling and limiting the amount of material which is picked up and moved laterally of the slab while permitting more or less material to pass beneath the pan.

It is a still further object to provide apparatus of the kind decribed, including a float pan that is partly supported from its end-s and having adjustable connections between a box beam and a screed pan which may be used to prevent or eliminate pan sag.

And yet another object of the invention is to provide apparatus of the kind described, including a float pan that is resiliently supported from a traveling machine or platform that is held on a predetermined grade line by grade control apparatus. 7

Other objects of this invention will become apparent in view of the following detailed description and the accompanying drawings.

In the drawings forming a part of this application and in which like parts are identified by like reference numerals throughout the same,

FIG. 1 is a side elevation of a typical installation of the invention on a slip-form paving apparatus for building roads;

United States Patent FIG. 2 is a perspective view of the preferred embodiment of the invention shown in FIG. 1 but disassociated from the conventional slip-form paving apparatus; and' FIG. 3 is a side elevation and detail of the float pan.

Referring to FIG. 1 in particular, there is illustrated one embodiment of the invention as used with a slip-form paving machine 10 of known construction. The machine generally comprises a supporting framework 11, a concrete distributing car 12 and a pan type screed member 13. The machine is conventionally mounted upon a pair of supporting side tracks (not shown) which advances the machine at relatively slow speeds along a prepared road bed 14. The vertical position of pan 13 relative to its supporting side tracks may be adjusted by a grade control apparatus such as disclosed in United States Patent No. 2,844,882.

In the customary manner of operation, concrete ma-' terial 15 is distributed over'the 'roadbed in advance of the screed pan 13 by distributing car 12. Then, as the machine advances the concrete is compacted and leveled to a predetermined depth by pan 13. A float pan 16 is used to smooth out the surface of the roadway, and an expansion joint is formed in the slab by a strip inserting blade 17. Although it is also customary to trail a second float pan in back of a strip inserting blade, as by means of cables 18, float pan -19 is uniquely constructed and resiliently supported in a manner hereinafter more part-icularly decribed as to provide a uniform finishing to the Q surface of the preformed slab.

Referring to FIGS. 2 and 3, float pan 19 is partly supported from a pair of arms 20 and-21, which extend rearwardly from framework 11 of machine 10. The ends of pan '19 are supported from arms 20 and 21, respectively,

- through resilient and adjustable connections, each connection comprising a chain hoist 22 and a coiled spring 23.

In operation, chain hoists 22 are adjusted so that a proportionate amount of pan weight is supported through springs 23, the balance of weight being applied to the slab. Since arms 20 and 21 are supported from machine 10, no ordinary change in grade will alter the amount of pan 'weight supported by the hoists and springs. On the other ing proportionally more or less pan pressure as the occasion demands and as determined by the condition of the slab surface being formed.

Where pan 19 is supported from only two support points the weight of the pan intermediate those support points may cause pan sag. Unless corrected, the pan would tend to form a concave surface in the slab, but this condition may be avoided by using the pan construction shown.

Referring to FIG. 3, pan 19 comprises a pair of box beams 24 'and 25 and a bottom plate 26 to which the beams are mounted by vertically adjustable connections. For this purpose, a number of mounting ears 27 are. provided along the sides of both box beams, and each ear is supported from a. vertical bolt or stud 28 by a pair of nuts 29. Each pair of nuts should be adjusted at a ime that a desired amount of pan weight is supported by springs 23, and in a manner such that the bottomof plate 26 is drawn into a straight line along its entire length. In general, this will mean that the center portion of box beams 24 and 25 will be connected vertically closer to plate 26 than those portions nearer to the supported ends.

'It will be noted that hoists 22 may be mounted from arms 20 and 21 so that the pan is moved at an angle relative to the direction of the roadway. In this manner, excess material which is picked up by the leading edge of the pan is worked across the preformed slab and deposited to one side of the roadways The angle with which pan 19 is supported may be varied, and for this purpose several depending support ears 30 are provided at the ends of arms 20 and 21. By selecting certain mounting ears for each hoist 22 pan 19 may be angled more or less to either side of a position normal to its direction of advancement.

The connecting linkage from which pan 19 is supported by springs 23 allows the pan weight supported by the slab to be adjusted relative to its leading edge. Moreover, it is to be understood that more or less concrete material will be picked up depending upon the distribution of the pan weight relative to its leading edge. Shifting the supported pan weight toward the rear of the pan permits a greater amount of concrete to pass beneath. Conversely, moving the pan weight toward the front or leading edge causes more material to be picked up.

FIG. 3 best illustrates the connecting linkage used. Springs 23 are each hooked through an opening in the end of a link member 351 pivoted from a flange 32 welded to box beam 24, and each link is adjustably positioned by means of a connecting rod 33 having one end pivoted to the link and the other end adjustably secured by a pair of nuts 34 to a flange 35 on box beam 26. An axial adjustment of nuts 34 along rod 33 will, of course, pivot links 31 as to move the point from which it is supported relative to the pans leading edge. As shown, an adjustment of nuts 34 may be used to place links 31 into either of the broken line positions illustrated, thereby shifting the point of spring support relative to the pans center of gravity and redistributing the pan weight supported by the slab.

Although a preferred embodiment of this invention has been illustrated and described, it is to be understood that various changes may be made without departing from the spirit of the invention or the scope of the attached claims, and each of such changes is contemplated.

What I claim and desire to secure by Letters Patent is: A

1. In combination with a paving machine, a pan disposed rearwardly of said machine and adapted for being towed thereby, a pair of support arms extending rearwardly from said machine, at least one of said support arms having several points of attachment for suspending said pan at an angle relative to its direction of advancement, means suspended from said points of attachment for resiliently supporting a part of the pans weight while said pan is also partly supported by a preformed slab of compacted concrete, and means for adjusting the proportion of pan weight supported by the resilient supporting means.

2. In combination with a travelling machine, a pan disposed rearwardly of said machine and adapted for being towed thereby, a pair of arms extending rearwardly from said machine, means suspended from said arms for resiliently supporting part of said pans weight While said pan is also supported upon a preformed slab of settable material, and means for supporting at least one end of said pan from several longitudinally spaced points along one of said arms to angle the pan relative to its direction of advancement.

3. In combination with a paving machine, a pan disposed rearwardly of said machine and adapted for being towed thereby,-means for resiliently supporting a part of the pans weight While said pan is also partly supported by a preformed slab of compacted concrete, means for adjusting the proportion of pan weight supported by the resilient supporting means, means at either end of said pan connecting said pan with said means for resiliently supporting said pan to thereby define a point of resilient support at said connection, and means for shifting said point of resilient support relative to the leading and trailing edges of said pan.

References Cited by the Examiner UNITED STATES PATENTS 2,160,462 5/1939 Schieferstein 9448 2,214,093 9/1940 Venable 94-48 2,226,466 12/1940 HeltZel 9445 2,844,882 7/1958 Early. I

2,847,917 8/1958 Heer 9446 3,041,946 9/1962 Watters 9446 3,135,177 6/1964- Kammerlin 9448 0 JACOB L. NACKENOFF, Primary Examiner. 

1. IN COMBINATION WITH A PAVING MACHINE, A PAN DISPOSED REARWARDLY OF SAID MACHINE AND ADAPTED FOR BEING TOWED THEREBY, A PAIR OF SUPPORT ARMS EXTENDING REARWARDLY FROM SAID MACHINE, AT LEAST ONE OF SAID SUPPORT ARMS HAVING SEVERAL POINTS OF ATTACHMENT FOR SUSPENDING SAID PAN AT AN ANGLE RELATIVE TO ITS DIRECTION OF ADVANCEMENT, MEANS SUSPENDED FROM SAID POINTS OF ATTACHMENT FOR RESILIENTLY SUPPORTING A PART OF THE PAN''S WEIGHT WHILE SAID PAN IS ALSO PARTLY SUPPORTED BY A PREFORMED SLAB OF COMPACTED CONCRETE, AND MEANS FOR ADJUSTING A PROPORTION OF PAN WEIGHT SUPPORTED BY THE RESILIENT SUPPORTING MEANS. 